FDA Approves ET-600 Desmopressin Acetate (Desmoda) for Central Diabetes Insipidus

Announced by parent company Eton Pharmaceuticals on February X, 2026, the US Food and Drug Administration (FDA) has approved ET-600 to treat central diabetes insipidus among pediatric patients.1

ET-600, now under the label Desmoda, is the first and only FDA-approved oral liquid formulation of desmopressin. It will be supplied as a ready-to-use oral solution of 0.05 mg/mL that does not require tablet splitting, crushing, refrigeration, mixing, or shaking.1

“In central diabetes insipidus, effective long-term management depends on accurately matching desmopressin dosing to each patient’s diurnal pattern of water balance,” Sean Brynjelsen, chief executive officer of Eton Pharmaceuticals, said in a statement. “Historically, clinicians have primarily relied on formulations that were not designed for fine dose adjustments or had other administration issues, and both clinicians and families often had to rely on workarounds. Desmoda introduces a liquid solution designed to deliver individualized dosing precision and consistency for patients across the age spectrum.”1

Central diabetes insipidus is a rare, complex disease wherein large volumes of dilute urine are excreted due to arginine-vasopressin deficiency (AVP-D). Its causes can be genetic, congenital, inflammatory, neoplastic, and traumatic, but mainly involve conditions arising from the hypothalamus.2

Early diagnosis and treatment are crucial for pediatric patients in particular, given the disease’s potential for central nervous system damage and the risk of dissemination of germ cell tumor. Additionally, the disease can progress into Langerhans Cell Histiocytosis and additional pituitary defects.2

Among the challenges presented by the disease is the differential diagnosis between central diabetes insipidus presenting with polyuria and polydipsia. This process requires a detailed medical history, biochemical approach, physical examination, imaging studies, and potentially histological confirmation. Pituitary stalk size is variable and can change depending on the underlying condition, and other brain areas or organs can become involved during follow-up.2

Desmopressin is a synthetic vasopressin analog first approved in 1978 to manage diabetes insipidus, as well as hemophilia A and von Willebrand’s disease. ET-600 is the first oral liquid formulation of desmopressin. Eton Pharmaceuticals has received a patent for the formulation extending to 2044, with an additional patent under review.3

The FDA’s decision was based on results from a bioequivalence study completed in March of 2025. Investigators from Eton enrolled 75 patients, who were then randomly assigned to receive the test and reference drug in an open-label, balanced, randomized, single-dose, 3-treatment, 3-sequence, 3-period, 3-way crossover oral bioequivalence study.4

Ultimately, ET-600 displayed full pharmacokinetic equivalence to the FDA-approved reference product of the same active ingredient. Following this, Eton submitted its first New Drug Application (NDA) for ET-600 to the FDA on July 8, 2025.3,4

“Central diabetes insipidus requires careful, individualized management, where dosing precision and flexibility truly matter. Having a liquid formulation of desmopressin has the potential to meaningfully support how we initiate and manage therapy,” Lewis Blevins, director of the California Center for Pituitary Disorders and professor of medicine and neurological surgery at the University of California, San Francisco, said in a statement. “It’s encouraging to see innovation that directly addresses real-world challenges faced by clinicians and families and gives greater confidence when tailoring treatment across age groups.”1

References

1. Eton Pharmaceuticals. Eton Pharmaceuticals Announces U.S. FDA Approval for DESMODA (desmopressin acetate) Oral Solution. February 25, 2026. Accessed February 25, 2026. https://ir.etonpharma.com/news-releases/news-release-details/eton-pharmaceuticals-announces-us-fda-approval-desmodatm

2. Patti G, Ibba A, Morana G, et al. Central diabetes insipidus in children: Diagnosis and management. Best Pract Res Clin Endocrinol Metab. 2020;34(5):101440. doi:10.1016/j.beem.2020.101440

3. Eton Pharmaceuticals. Eton Pharmaceuticals Announces FDA Acceptance of New Drug Application for ET-600 (Desmopressin Oral Solution). July 8, 2025. Accessed February 24, 2026. https://ir.etonpharma.com/news-releases/news-release-details/eton-pharmaceuticals-announces-fda-acceptance-new-drug-1

4. Eton Pharmaceuticals. Eton Pharmaceuticals Announces Positive Pivotal Clinical Study Results for Product Candidate ET-600. March 14, 2025. Accessed February 24, 2026. https://ir.etonpharma.com/news-releases/news-release-details/eton-pharmaceuticals-announces-positive-pivotal-clinical-study